Wow - tough crowd! We have 12+ pages of posts and this is the first direct comparison, if I am not mistaken. And I am been hammered for 10% or so difference in framing, and for wasting bandwidth!

I didn't want to cause undue alarm or attack you, and the surgar-coated version is also available ... I just tried pointing out that some tiny headroom for even further future improvement exists, but your input is very much appreciated and even at the current state great and very helpful :-)

Maybe I'm a bit over-critical, but I often observe researchers that for some matter discover exactly what they went out to find and knew before - it was a bit like that with your comparison shots: We know the 135L has better bokeh, so why bother with a real comparison to prove it :-p ?

Good you said that it was obvious. Now turn around and tell that to people who are hammering everyone who tries to tell this 'obvious' mathematical fact (as far as subject isolation is concerned; bokeh cant be quantified). They claim that difference is so subtle that most people cant pick it up in blind tests. Then, they either show crappy examples or 135 used at f/8 to match the DOF (dah, its going to be equal because you matched it) to make a point. Plamen shows first direct and relevant comparison and gets hammered by you for showing the 'obvious'. Fair world......

Wow - tough crowd! We have 12+ pages of posts and this is the first direct comparison, if I am not mistaken. And I am been hammered for 10% or so difference in framing, and for wasting bandwidth!

I didn't want to cause undue alarm or attack you, and the surgar-coated version is also available ... I just tried pointing out that some tiny headroom for even further future improvement exists, but your input is very much appreciated and even at the current state great and very helpful :-)

Maybe I'm a bit over-critical, but I often observe researchers that for some matter discover exactly what they went out to find and knew before - it was a bit like that with your comparison shots: We know the 135L has better bokeh, so why bother with a real comparison to prove it :-p ?

Good you said that it was obvious. Now turn around and tell that to people who are hammering everyone who tries to tell this 'obvious' mathematical fact (as far as subject isolation is concerned; bokeh cant be quantified). They claim that difference is so subtle that most people cant pick it up in blind tests. Then, they either show crappy examples or 135 used at f/8 to match the DOF (dah, its going to be equal because you matched it) to make a point. Plamen shows first direct and relevant comparison and gets hammered by you for showing the 'obvious'. Fair world......

Why not just try and tell me which of the four images I posted many pages ago are shot with which lens, surely that should be easy seeing as how the 135 has a "unique look"? And that is my point, yet again, it is not about comparisons, it is about the FACT that nobody can RELIABLY tell what image was shot with which lens, nobody who alludes to this "unique look" can reliably identify it, if you can't reliably identify it it isn't "unique".

I answered that already, several times. It is not hard to use a lens with a unique look in a way that nobody can tell the difference with a f/4 zoom. It has unique look when you use it in a unique way.

I have comparisons of the 24-105 with the 50L, the 85LII, the 35L. You would not be able to tell a difference, and even under 100% it will be hard to say which is which. I can post them if you insist. So what now, since nobody can tell the difference in those shots, those three primes are useless?

Why not just try and tell me which of the four images I posted many pages ago are shot with which lens, surely that should be easy seeing as how the 135 has a "unique look"? And that is my point, yet again, it is not about comparisons, it is about the FACT that nobody can RELIABLY tell what image was shot with which lens, nobody who alludes to this "unique look" can reliably identify it, if you can't reliably identify it it isn't "unique".

I answered that already, several times. It is not hard to use a lens with a unique look in a way that nobody can tell the difference with a f/4 zoom. It has unique look when you use it in a unique way.

I have comparisons of the 24-105 with the 50L, the 85LII, the 35L. You would not be able to tell a difference, and even under 100% it will be hard to say which is which. I can post them if you insist. So what now, since nobody can tell the difference in those shots, those three primes are useless?

Don't waste your time with PBD. You've showed your photos to prove your point and explained yourself. He has nothing to show to support his views. He's just too stubborn to realize whats plainly in front of him.

First, the "comparison" plamen posted IS NOT relevant or the situation I have constantly referred to, I KEEP saying FOR THE SAME FRAMED IMAGE, that means moving forwards for the 100.

Exactly what I did. The error was about 10%.

I will post some more.

Why not just try and tell me which of the four images I posted many pages ago are shot with which lens, surely that should be easy seeing as how the 135 has a "unique look"? And that is my point, yet again, it is not about comparisons, it is about the FACT that nobody can RELIABLY tell what image was shot with which lens, nobody who alludes to this "unique look" can reliably identify it, if you can't reliably identify it it isn't "unique". If the look it gives isn't unique then there needs to be a better reason to choose between the two lenses. My thought was that, bearing in mind nobody seems to be able to differentiate the lenses when used for portraits, the macro has much more flexibility. Now why is that so controversial?

You are dead wrong. Even if I accept your suggestion that one should buy 135 mm to walk away and match the composition of 100 mm (there is a reason why people buy suitable focal length) and hence make the imaging scale (physics term) same and hence the same depth of field. That is true because DOF for same imaging scale and same aperture (although f stop is not same in your examples) is unrelated to focal length. That seem be where you are falling down. Same DOF does not mean same OOF blur. The OOF blur or specifically, the infinity background blur (only measurable component defining bokeh) is dependent on physical size of entrance pupil in the imaging setup. That means the larger imaging formats, higher apertures and longer focal lengths will give you more out of focus blur, an essential prerequisite for good bokeh in addition to the lens design. With 135, you have bigger aperture as well as larger focal length and hence considerably more OOF blur even for same DOF. Now you can either read optics textbooks, or take comparable shots to test it as Plamen tried to show you. You can do better if you are not satisfied. Posting random shots of other people from here and there and asking which lens was it is not a proper experimental design. Even if you want to do blind test just take the shots on 100 and 135 with same DOF and ask people which one has better bokeh. That would tell you if its subtle or not. I repeat my analogy since you are not understanding it - What you are saying is essentially that Ferrari is as good as Hyundai. And as a proof you show a Ferrari stuck in one of those famous LA traffic jams with Hyundai. Does that make sense to you?

Logged

split personality

First of all, there's no magical thing such as "lens compression". It is simply due to the working distance between the camera and the subject that changes the perspective. A 24mm wide angle can achieve the same "lens compression" by taking the shot at the same distance with extreme cropping afterwards. The big penalty here is obviously resolution. For the 100mm to achieve the same perspective and "lens compression" as the 135mm, expect to crop out ~10% of your final picture. Honestly I didn't bother to do the math.

As of distinguishing between F/2 vs F/2.8 in terms of DOF, it is not always easy to the naked eye. Will your client complaint about the background not being blurry enough despite the strong composition, perfectly lit, well focused and expressive shot? Of course not! But is shallower depth of field more pleasing to the eye when isolating our subjects from the background? You bet!

Simply move your mouse between each stop and don't tell me you cannot see the difference in the background blur. Perhaps Canon should stop selling the 200mm F/2 when everyone can simply get the superb 70-200mm F/2.8 II that actually zooms, much lighter, less expensive and pretty darn sharp and well built then just leave it at 200mm F/2.8. Obviously for those who tried the 200mm F/2 would disagree.

Besides DOF, F/2 is still one stop over F/2.8. I'm sorry but that's quite significant. We all know that IS doesn't stop motion blur so that extra stop of light can mean the difference between a blurry portrait shot at 1/50s vs a sharp one at 1/100s. In a very poorly lit church where no flash is allowed, a barely sharp 1/100s shot of the bride walking down the aisle vs a tack sharp 1/200s shot makes a huge difference.

At this point, you might say... meh.. why not just compensate with higher ISO? Awesome, let's talk about ISO.

The one stop advantage of the F/2 sometimes allows you to shoot at ISO 6400 instead of ISO 12800. You will certainly see a difference even on the 1DX or 5DIII. On the current 18MP APS-C crops, the difference is significant between ISO 1600 and 3200. Let's not even talk about 6400.

Call me old-fashioned but I prefer my portraits to be well composed in the camera without cropping, have a shallower DOF to isolate my subject, tack sharp with a faster shutter and maintaining a lower ISO for maximum image quality.

With the 100mm F/2.8 you are essentially compromising a combination of the above to achieve the same as the 135mm F/2. The biggest advantage which I won't deny is the macro capability. Now if you want to shoot extreme closeups (like filling the entire frame with one eye)... sure just get the 100mm F/2.8.

As far as portraiture is concerned, and let's stick with the classic definition of portraits, the 135mm F/2 is still a winner.

Are some of you going blind? The short answer is yes, a macro lens can be used as a portrait lens, technically. But when you're taking a photo of a person who is facing your camera, and your trying to get a natural look.... Macro lenses are horrible for that. Most of them are too sharp, oversaturate and don't render skin tones naturally. If you can't see that in the sample comparisons alone I suggest getting your eyes checked. That's why specialty lenses are designed specific ways, to excel in the areas they were designed for. Simple as that.

I write this entry as a disinterested (i.e., impartial) observer, and also to echo comsense’s hope for peace between RLPhoto and privatebydesign.

I see between the two writers something of what I have seen in other contexts when reasonable persons discuss questions of how human expression is realized in artistic or creative contexts. My observations are neither meant nor intended to be definitive. Rather, I present my perception as a “best-guess-paraphrase” of the lively exchange in this thread on Canon’s 135 f/2L and 100 f/2.8L Macro IS lenses. My characterizations of RLPhoto and privatebydesign rest only on what I have read or seen from them on this site and on what I have seen on any of their personal sites they have referenced.

From my reading of RLPhoto’s entries in this and in other threads, as well as from my perusal of his website, I understand him to be a photographer-as-artist. His work is photography qua photography, and his language coincides with that identity. Many of RLPhoto’s posts have noted the question of “good photography”. Indeed, RLPhoto reminds me pianists (for example), who play beautifully, regardless of what instrument they have at hand, be it a Yamaha, a Steinway, or a Bösendorfer. At no point would such pianists deny differences in physical and acoustic properties of the instruments. It is not uncommon, though, that such a pianist–let’s call him Chuck–might make statements such as “I get the best tone from the action on a Bösendorfer. A Steinway keyboard doesn’t let me be as expressive of maestoso aspects”. So, when RLPhoto refers to a “unique look” in his use of the 135L, I take his use of language in the context of how photographers qua photographers express themselves. Put another way, when talking about their field, such photographers may at times tend to use language in non-literal ways, despite their word choices. I do not pretend to speak for RLPhoto, but I offer the proposition that, when he cites “35% more compression”–for example–his statement does not derive from measurements taken in a physics or optics laboratory. He is speaking more loosely, I speculate, than would a physicist on the same matter. When he speaks of a “unique look”, he speaks as Chuck does in describing the action of a Bösendorfer.

Alternatively, privatebydesign, in the majority of his posts, appears to express himself in rather literal ways. He offers advice and opinion based on technical, specified, published, or other such concrete, testable information or data. Naturally, then, for someone who uses language in a more literal way–let’s call him Fred–on hearing statements such as that made by Chuck, might respond along the lines of, “What do you mean you can’t be as expressive on a Steinway? In what way? By what criteria? Are you suggesting that you can’t get the same sound and expressiveness on a Steinway as you can on a Bösendorfer?”

And there it begins. Chuck might say, “When I play a Bösendorfer, I get the tone I want, a tone that I know, a tone I can hear. I don’t need to measure anything. I know what I’m playing and what I’m hearing. Fred might say, “If we record two persons playing the same passage, the Steinway pianist can get, with minor accommodations, the same or similar level of expressiveness as you can on your Bösendorfer.” “No, he can’t.” “Yes, he can.” And so it goes.

Before continuing, let me clarify that my analogy is not that of comparing pianos from different manufacturers with lenses from a single manufacturer. My analogy goes merely to the matter of two different objects producing similar–or not–results. Furthermore, the piano-lens comparison is not at issue here.

But a focus on language is.

I imagine that RLPhoto and privatebydesign might agree on a good deal in photography. What seems to have happened is that RLPhoto’s use of language strikes privatebydesign as imprecise and, even, as an instance of spreading inaccurate or misleading information. I do not take RLPhoto to be someone who would spread misinformation deliberately, and neither do I take him to be “wrong” in his statements. He speaks what is true for him, what is true for his experience, and what is true for his work. I speculate further that he does not propose to speak in the manner of a scientist, and that he does not respond or conduct his posts in a scientistic mode.

Alternatively, privatebydesign’s observations on the 100 and 135 lenses seem to be grounded on principles of mathematics and physics. His statements on the lenses are also not based, I believe, on anything in the way of feeling or art. What he expresses is true, verifiable, and not inherently inflammatory.

Both gentlemen, then, have expressed truths, but they have “talked past each other”, so to speak. I stand with others in this thread in being surprised by the continued tension between RLPhoto, privatebydesign, and their occasional supporters.

I suggest that a difference in the way each contributor uses and understands language in the context of how they view and practice their fields placed them, inadvertently, in a less than sunny exchange. If this is in fact the case, then perhaps reconciliation between parties is possible.

Well said. That's my take as well. I can understand the idea about the 'feel' of a lens. That's the romance of it. Not everything can or should be boiled down to hard science. But I can appreciate PBD's viewpoint too. Both are wrong. And right.

Thanks, there are some with more comparable framing (esp. the book shelf)!

The 100L, being mainly a macro lens, doesn't need a very large open aperture since for objects near the lens the bokeh is bound to be strong, and the problem usually is a too tiny dof. But I'm not surprised that for head+shoulders portraits the 100L cannot eliminate the background, that's why it's "only" dual use and there are fast primes. But it's also my experience that f2.8 for portrait distance still "integrates" the background.

The 100L is a great "budget" (€900, argh) alternative, esp. since I've got the Kenko 1.4x tc to have stronger compression or macro working distance when I need it.